Fusible cut-out for electrically-heated articles



Patented Mar. 4, 1924.

UNITED STATES 1,485,784 PATENT OFFICE.

CHARLES EDWARD IREDELL, OF REGENTS PARK, LONDON, ENGLAND.

FUSIBLE CUT-OUT FOR ELECTRICALLY-HEATED ARTICLES.

Application filed July 19, 1923. Serial No. 652,543.

To all whom it may concern.

Be it known that I, CHARLES EDWARD IRE- DELL, a subject of the King of Great Britain, residing at 7 Cumberland Terrace, Regents Park, in the county of London, En land, have invented certain new and usefu Improvements in or Relating to Fusible Cut- Outs for Electrically-Heated Articles, of which the following is a specification.

This invention relates to fusible cut-outs for electric irons or other electrically heated articles of the kind in which a plug or the like of fusible material is employed together with mechanical means controlled or released by the fusing of said plug'or the like which act to break the electric circuit through the heating resistance.

According to the present invention the cut-out comprises a pair of members which are capable of relative endwise movement and which are normally maintained in electrical contact with one another by means of a fusible plug, the members being in circuit with the heating resistance, and subjected to the influence of sprin means which tend to separate them, and t e arrangement being such that on the plug being fused, due to over-heating of the article to which the cut-out. isapplied, said spring means cause the members to separate thereby breaking the electric circuit through the heating resistance. The fusible plug may be U-shaped and composed, for example, of an alloy of tin, zinc and bismuth, and the cut-out is preferabl positioned in an easily accessible part of t e electric iron or other device.

In order that the said invention maybe clearly understood and readily carried into effect the same will now be described more fully with reference to the accompanying drawing which shows, by way of exam 1e, one form of the fusible cut-out as app ied to an electric iron and in which Figure 1 is a part sectional elevation taken on the line aa of Figure 2.

Figure 2 is a plan view of Figure 1 with the handle and top cover of the iron removed.

Figure 3 is a section on the line b-b of F i are 1 and igure 4 is a view of a modified construction of fusible cut-but.

Referring to the drawing, 1 is the base plate or sole of the iron; 2 is the enclosing cover; 3 is the handle; 4 is the heating resistance and 5 is the cover plate which encloses the heating resistance 4:. 6, 6 are the usual bolts for securing together the parts of the iron and 7 is one of the terminal plugs for connecting the iron to an-outside circuit. 8, 8 are the contact pieces and 9 is one of two spring members carried by the terminals 7 7 which bear upon the contact pieces 8, 8*. The fusible cut-out in the example shown at Figures 1 to 3 comprises a base plate 10 secured by means of a screw 11 to the cover plate Mounted on the base plate 10 are a pair of upstanding lugs 12, 13 secured thereto by screws 14 and 15. 16 and 17 are the relatively movable mem bers which are normally held in contact with one another by the compression spring 18. In the example shown the members 16 and 17 are constituted by spindles having enlargements 16 and 17 at one end thereof and being screw threaded at their other extremities. The contact member 17 is insulated from the lug 13 by plugs 20 and 21 held in place by lock nuts and washers 22. The other movable member 16 is mounted within a screw threaded bush 23 which engages a screw threaded opening in the up standing portion 12. The spring 18 is located between the bush 23 and a nut 24 on the screw threaded extremity of the member 16. 19 is a U-shaped fusible plug 10- cated around the member 16, which normally tends to hold the members 16 and 17 in contact with one another against the resistance of the spring 18. On the fusible plug 19 being fused the spring 18 separates the members 16 and 17 and breaks the electric circuit through the heating resistance. A lead 40 is taken from the contact member 17 to the contact piece 8 and a lead 41 from the lug 12 to the heating resistance. 25, 26 are strips of insulating material such as mica which serve to insulate the lead 41 from the cover plate 5 and the contact strip 8. As soon as the fusible plug 19 melts it will be seen that the enlargement 16 of the movable member or plunger 16, will be forced by the action v0t the spring 18, into engagement with the adjacent surface of the threaded collar or bush 23. In order to insert a new plug in position, pressure is applied at the outer end of the plunger 16, which causes the enlargement 16* to be moved away from the collar 23, so as to readily permit the new plug to be inserted on the plunger 16.

Figure 4: shows a modified arrangement .for said members,

comprising a base plate 27 secured at 28 to the cover plate 5. Mounted upon the base plate 27 are the pair of terminals 29 and 30 to which are attached the leads 37 and 38. The terminal 30 is insulated from the base plate 13 by a plu and washers 31 and is held in place on t e base late by a screw 32. 33 and 3e are the re atively movable members and 35 is the spring which normally tends to separate the said members. 36 is the fusible plug which holds them in contact. On the plug being fused the spring 35 separates the contact members and breaks the circuit through the heating resistance. The other contact member 33 is mounted within a screw threaded bush in the terminal 30 so as to enable the contact member 33 to be retracted to facilitate the insertion of a new fusible plug.

. What I claim and desire to secure by Let-.

ters Patent of the United States is 1. A fusible cut-out of the class described comprising a pair of coaxially extending members having their adjacent ends normally in contact with each other, supports a collar on one of said supports through which the movable member loosely extends, a fusible plug on the movable member between its inner end and the collar, and means for separating said members when the plug is fused.

2. A fusible cut-out of the class described comprising a pair of coaxially extending members having their adjacent ends normally in contact with each other, supports for said members, a collar on one of sai supports through which the movable member loosely extends, a substantially U- shaped fusible plug on the movable member between its inner end and the collar, and means for separating said members when the plug is fused.

3. A fusible cut-out of the class described comprising a base,-a pair of lugs projecting upwardly from said base, a stationary cutout member threadedly secured in one of said supports, a collar threaded in the other of said supports, a movable contact member loosely extending through said collar, said contact members having their adjacent ends normally in contact with each other, a fusible plug on the movable member, means for yieldably maintaining said fusible plug between the inner end of the movable member and the collar, and means for separating said contact members when said plug is fused.

4. A fusible cut-out of the class described comprising a base, a pair of lugs projecting upwardly from said base, a. stationary contact member threadedly secured in one of said supports, a collar threaded in the other of said supports, a movable contact member loosely extending through said collar, said contact members having their adjacent ends normally in contact with each other, a substantially U-shaped fusible lu in the movable member, means for yie da ly maintaining said fusible plug between the inner end of the movable member and the collar, and means for separating said contact members when said plug is fused.

CHARLES EDWARD IREDELL. 

